This invention relates to an ultrasonic treatment instrument for performing treatments such as incision, excision, coagulation, etc.
U.S. Pat. No. 3,636,943, for example, discloses a general ultrasonic treatment instrument constructed as below. This ultrasonic treatment instrument comprises a substantially cylindrical sheath, and an ultrasonic probe mounted in the sheath such that it can slide along the axis of the sheath.
The sheath has, at its tip, a hook-shaped reception member of a substantially L shape. At the time of using the ultrasonic treatment instrument, the ultrasonic probe is slid relative to the sheath along the axis thereof, thereby holding an organic tissue such as a blood vessel between a tip portion of the probe and the hook-shaped reception member. Further, in this state, ultrasonic oscillation is transmitted to the tip portion of the probe, thereby subjecting the organic tissue held therebetween to an ultrasonic treatment such as a ligation thereof.
The instrument of U.S. Pat. No. 3,636,943 has a structure in which ultrasonic oscillation is transmitted, in an ultrasonic treatment, to the tip portion of the ultrasonic probe, and not to the hook-shaped reception member at the tip of the sheath. In other words, the hook-shaped reception member is kept still. This means that it is difficult for this instrument to peel a thin organic tissue using the hook-shaped reception member since the thin tissue may well slip from the reception member.
Moreover, U.S. Pat. No. 5,322,055, for example, discloses an ultrasonic treatment instrument with a structure in which a soft contact member for absorbing noise is attached to a hook-shaped reception member provided at the tip of a sheath. In this case, however, it is impossible at the tip of the hook-shaped member to perform peeling, etc. of an organic tissue using ultrasonic oscillation, or to perform a treatment using high frequency current. Thus, it is difficult to impart many functions to the ultrasonic treatment instrument.